Letterkenny takes its name from the Irish "Leitirceanainn" – meaning the "Hillside of the O'Cannons" – the O'Cannons being the last of the ancient chieftains of Tir Conaill. Although the O'Cannons were the last chieftains of Tir Conaill no evidence of forts or castles belonging to the clan exists in or around the Letterkenny district. (Leading to speculation on a possible derivation of the name Letterkenny: from the Irish "Leitir Ceann-Fhoinn" meaning "Fairheaded Hillside"). Letterkenny Town Centre ca. 2005Letterkenny began as a market town in the 17th century (before the Great Famine) and was the first crossing point of the River Swilly. In the recent past the population of Letterkenny consisted of cattle and sheep grazing on what were then untilled hillside - when Conwall (2 miles west of Letterkenny) was the ecclesiastical and seaport centre. The waters of the Atlantic had not yet reached from the basin of the Swilly whose estuary at that time extended up almost as far as New
